<template>
  <div id="app">
    <div class="container">
      <!-- 顶部框模块 -->
      <div class="form-group">
        <div class="input-group">
          <h4>品牌管理</h4>
        </div>
      </div>

      <!-- 数据表格 -->
      <table class="table table-bordered table-hover mt-2">
        <thead>
          <tr>
            <th>编号</th>
            <th>资产名称</th>
            <th>价格</th>
            <th>创建时间</th>
            <th>操作</th>
          </tr>
        </thead>
        <tbody>
          <tr v-for="item in list" :key="item.id">
            <td>{{ item.id }}</td>
            <td>{{ item.name }}</td>

            <!-- 如果价格超过100，就有red这个类 -->
            <td :class="{ red: item.price > 100 }">{{ item.price }}</td>
            <td>{{ formDate(item.time) }}</td>
            <td><a href="#" @click="remove(item.id)">删除</a></td>
          </tr>
          <tr>
            <td colspan="3">总价 {{ sum }}</td>
            <td colspan="3">均价 {{ asum }}</td>
          </tr>
        </tbody>

        <tfoot v-if="list.length === 0">
          <tr>
            <td colspan="5" style="text-align: center">暂无数据</td>
          </tr>
        </tfoot>
      </table>

      <!-- 添加资产 -->
      <form class="form-inline">
        <div class="form-group">
          <div class="input-group">
            <input type="text" class="form-control" placeholder="资产名称" v-model.trim="name" />
          </div>
        </div>
        &nbsp;&nbsp;&nbsp;&nbsp;
        <div class="form-group">
          <div class="input-group">
            <input type="text" class="form-control" placeholder="价格" v-model.number="price" />
          </div>
        </div>
        &nbsp;&nbsp;&nbsp;&nbsp;
        <!-- 阻止表单提交 -->
        <button class="btn btn-primary" @click.prevent="add">添加资产</button>
      </form>
    </div>
  </div>
</template>

<script>
import moment from 'moment'
export default {
  data() {
    return {
      name: '', // 名称
      price: '', // 价格
      // list: [
      //   { id: 100, name: '外套', price: 199, time: new Date('2010-08-12') },
      //   { id: 101, name: '裤子', price: 34, time: new Date('2013-09-01') },
      //   { id: 102, name: '鞋', price: 25.4, time: new Date('2018-11-22') },
      //   { id: 103, name: '头发', price: 19900, time: new Date('2020-12-12') }
      // ]
      list: JSON.parse(localStorage.getItem('list') || '[]')
    }
  },
  watch: {
    list: {
      deep: true,
      handler() {
        localStorage.setItem('list', JSON.stringify(this.list))
      }
    }
  },
  methods: {
    add() {
      if (this.name.length === 0 || this.price <= 0 || typeof this.price == 'string')
        return alert('资产名或价格不能为空0')
      let id = this.list.length > 0 ? this.list[this.list.length - 1].id + 1 : 100
      this.list.push({
        id: id,
        name: this.name,
        price: this.price,
        time: new Date()
      })
      this.name = ''
      this.price = ''
    },
    remove(id) {
      let index = this.list.findIndex(obj => obj.id === id)
      this.list.splice(index, 1)
    },
    formDate(val) {
      return moment(val).format('YYYY-MM-DD')
    }
  },
  computed: {
    sum() {
      return this.list.reduce((prev, cur) => prev + cur.price, 0)
    },
    asum() {
      return (this.sum * this.list.length).toFixed(2)
    }
  }
}
</script>

<style>
.red {
  color: red;
}
</style>
